Fuse

A fuse is a one-time overcurrent protection device. It contains a thin metal element that melts when current exceeds its rating, breaking the circuit to protect wiring from overheating. Once blown, a fuse must be replaced with one of the same rating. Fuses come in many forms — cartridge, plug, blade, and glass tube — and are used in homes, vehicles, electronics, and industrial equipment. Never replace a fuse with a higher-rated one.